Nuclear non-proliferation has become one of the world's chief concerns, amid worries about nuclear weapons falling into the hands of terrorists and the nuclear ambitions of countries such as North Korea and Iran. In Moscow, more than 300 experts and officials are meeting to discuss issues ranging from monitoring and verification to export controls.

The first day of discussions found participants agreeing about one thing, the threat of nuclear proliferation and heightened concerns about the use of weapons of mass destruction require an urgent look at global non-proliferation regimes.

The 1968 treaty on the Non-Proliferation of Nuclear Weapons, also known as NPT, remains the cornerstone of non-proliferation efforts. But many nations worry about noncompliance.

North Korea withdrew from the Nuclear Non-Proliferation Treaty earlier this year, after admitting to U.S. officials that it had a nuclear weapons program. Meanwhile, the International Atomic Energy Agency, or IAEA, has given Iran until the end of next month to prove it is not secretly trying to acquire or develop nuclear weapons.

The keynote speaker of the day was the United Nations undersecretary- general for disarmament affairs, Nobuyasu Abe. Mr. Abe says the most pressing non-proliferation concern is the need for stronger monitoring and verification procedures. "It is extremely important that as many countries as possible urge those countries, which are hesitating to conclude additional protocols, particularly those with significant nuclear activities, to do so as soon as possible," he said. "Iran and the Democratic People's Republic of Korea are a case in point. There is an urgent need for Iran to accept the recent IAEA Governing Board resolution, and conclude and implement an additional protocol, and, for North Korea to return to the NPT."

The head of the Russian Foreign Ministry's Political and Military Affairs Department, Evgeniy Zvedre, said the aim of the Moscow meeting is to discuss ways to improve non-proliferation measures.

"We are not here to blame any particular country for what it is doing, or for what it is not doing," said Mr. Zvedre. "But we are here to look for the way out of this situation, for better means to curb the proliferation of WMD [weapons of mass destruction], and to provide at the same time the legitimate needs of all countries, without any exception needs for their security, for their substantial economic development, and just for a better future."

In remarks during a roundtable session, the U.S. ambassador to Russia, Alexander Vershbow, reiterated Washington's desire to see Russia freeze its nuclear cooperation with Iran. He also urged Moscow to use its influence with Soviet-era ally Korea to persuade Pyongyang to abandon its nuclear weapons program.